Toggle clamp



May 20, 1958 L. F. BLATT ETAL TOGGLE CLAMP 2 Sheets-Sheet 1 Filed Dec. 22, 1955 INVENTORS LELAND I. BLATT ARTHUR E. SHERMAN y 0, 1958 L. F. BLATT ETAL 2,835,291

TOGGLE CLAMP Filed Dec. 22, 1955 2 Sheets-Sheet 2 I INVENTORS LELAND E BLATT,

ARTHUR E. SHERMAN ATTORNE 2,835,291 Patented May 20, 1958 like TOGGLE CLAMP Leland F. Blatt, Grosse Pointe Woods, and Arthur E. Sherman, Detroit, Mich.

Application December 22, 1955, Serial No. 554,710 Claims. (Cl. 144-302) This invention relates to toggle clamps for holding one or more work pieces in a required position .for various operations, as welding, drilling, riveting, etc.

An object of the invention is to provide a clamp comprising a pair of jaw members pivotally interconnected to swing relatively between releasing and clamping positions, one such member pivotally mounting a lever taking efiect on the other member through a swinging link, and said other member having an actuating arm pivoted to such link, the arm and link having a toggle coaction such that an oscillation of the lever to and from one of its limiting positions will continuously advance the swinging jaw member from its released to its clamping position or vice versa.

Another object is to form the lever-mounting jaw member with an opening to accommodate said link in the releasing position of the clamp.

Another object is to form said lever with a handleforming arm and a relatively short arm connected to said link and forming with the latter a toggle pair to apply heavy pressure to the swinging jaw as the latter takes effect on work, and further resisting accidental escape of the swinging jaw from either of its limiting positions.

These and various other objects are attained by the construction hereinafter described and illustrated in the accompanying drawings, wherein:

Fig. l is a side elevational view of the improved clamp, showing the clamping and releasing positions of the jaw members respectively in full and dash lines.

Fig. 2 is a top plan view of the clamp, conforming to the full line showing of Fig. 1.

Fig. 3 is a rear view of the same.

Fig. 4 is a view similar to Fig. 1 but showing the control lever swung to its other limiting position and the parts correspondingly shifted.

In these views, the reference character 1 designates an elongated substantially rectangular jaw member comprising a pair of lugs 1a projecting lengthwise of such member to one end thereof, a slot 2 being formed between such lugs. Terminally pivoted upon and between said lugs by a pin 3 is a jaw member 4 coacting with the member 1. The member 4 has transverse portions, one engaging said pin and the other having a work-engaging face 5 paired with a face 6 of the member 1, and formed to some extent by the lugs 1a. At its end remote from the pin 3, the jaw member 1 integrally carries a pair 6 of spaced lugs 7 projecting from a face of said member opposed to its face 6. Fulcrumed upon and between the lugs 7 by a pin 8, is the relatively short work arm 9 of a bell crank lever whose power arm 10 provides a handle for'applying and releasing the clamp. A pair of spaced links 11 have corresponding ends straddling the lever at the juncture of its arms and pivoted to the lever by a" pin 12. At their other ends, the links straddle an arm 13 integrally carried by and serving to actuate the jaw member 4, said arm and jaw member being substantially opposed with reference to the pin 3. A pin 14 pivotally interconnects the links 11 and arm 13. The width of the slot 2 is adequate to afford insertion therein of the links 11 and pin 14. A shallow boss 15 on the member 1 serves as a stop engageable by the arm 9 to limit clockwise swinging of the lever.

5 In use of the described clamp, one or more workpieces,

as exemplified at 16 and 16a, are placed against or adjacent to the face 6, and the lever is then swung counterclockwise to shift the jaw member 4 from its released position (Fig. l in dash lines) to its mid-position shown 10 in Fig. 4. As said mid-position is established, the links 11 and arm 13 are, in effect, aligned, thus opposing further counter-clockwise actuation of the lever, the momentum of said parts, however, carrying them upward slightly beyond alignment and initiating reverse travel of 15 the lever. The operator now immediately completes reverse actuation of the lever, thus maintaining said momentum and compelling the linkage the collapse upwardly responsive to said reversed actuation. Thus the linkage is raised clear of the slot 2, advancing the swinging 20 jaw to its clamping position. As the work: is placed under clamping stress, the handle 10 again assumes its upright position, the links aligning, in efiect, with the arm 9 to increase and maintain the applied stress, as per the full line showing of Fig. 1. To release the work and return 5 the swinging jaw member to its raised position, the described manipulation of the lever is repeated, the forward stroke of the handle 10 establishing the mid-position of the swinging jaw member and inducing down travel of the links and arm 13 slightly beyond alignment thereof,

and the return stroke of the handle completing up travel ,of the swinging jaw, while thrusting the joined ends of the links and arm 13 downwardly through the slot 2.

When said ends are thus thrust down, the links assume an approximately transverse relation to the work arm 9. A highly desirable advantage of the described clamp is the actuation of the swinging jaw through one hundred and eighty degrees responsive to a lever oscillation less than ninety degrees. Locating the swinging jaw member, as fully released, remotely from its clamping position as- 0 sures a maximum clearance for establishing the clamping position of a part or parts, so carried by relatively large members (not shown), such as sheet metal panels, as to require such clearance. Minimizing the requisite angular travel of the lever is for like reasons desirable.

It is to be understood that in operating the described clamp, it is necessary to apply a snap or abrupt movement to the lever, imparting such momentum as will carry the described linkage past its dead center mid position.

Employing the same lever travel for both clamping and releasing purposes simplifies use of the clamp and minimizes the likehood of any mistake in such use. It is an important feature of our construction that the toggle action thereof locks the swinging jaw in its open position,

positively maintaining such position until a definite control is applied, and avoiding undesired shifting of said jaw due to vibration or other influences. While employment of a toggle mechanism to maintain the clamping position of coacting jaws is well known, originality is believed to be achieved by a toggle linkage maintaining both limiting positions of the jaws.

What we claim is:

l. A toggle clamp comprising first and second meeting jaw members, the first member having opposed ends and a slot extending from one such end toward the op- 65 posite end, and the second member being received in said slot and having an actuating arm, means pivotally interconnecting said members aifording a swinging of the second member alternatively to a clamping or a released position, a lever having a power arm and work arm, means 70 pivotally mounting the lever on the first member at the end of such member remote from the slot, and a swinging link interconnecting said lever and actuating arm and having a toggle coaction with the work arm, whereby said link and work arm are substantially aligned, in effect, to establish said clamping position, the lever occupying the same limiting position thereof in establishing both the clamping and released positions of the jaws, and the link being received by the slot in said released position.

2. A toggle clamp comprising first and second coacting jaw members, means pivotally interconnecting such members, a lever having a power arm and a work arm, means pivoting such lever on the first jaw member, an actuating arm rigidly carried by the second jaw member and projecting from said interconnecting means in an approximately reverse direction to the second jaw member, and a swinging link interconnecting the lever with said actuating arm, the second jaw member having substantially a 180 degree swing between limiting clamping and re leased positions thereof, said lever having a first limiting position established by impact of its work arm against the first jaw member, such position alternatively establishing either one of said limiting positions of the second jaw member, the lever work arm and link being substantially aligned, in effect, in one of said limiting positions of the second jaw member and being approximately right angularly related in the other of said limiting positions of the second jaw member, the lever having a second limiting position in which said link and actuating arm are aligned in effect, the lever being actuable from its first to its second limiting position and back to its first position to shift the second jaw member from either limiting position thereof to its other limiting position.

3. A toggle clamp as setforth in claim 2, said link extending, in the released position of the second jaw member, between the pivotal connections of such jaw member and of the lever to the first jaw member.

4. A toggle clamp comprising first and second coacting jaw members, means pivotally interconnecting such members, a lever having a power arm and work arm, means pivoting the lever on the first jaw member, an actuating arm rigidly carried by the second jaw member, and a swinging link interconnecting the lever with said actuating arm, the second jaw member having angularly spaced work clamping and released positions at the ends of its travel about said interconnecting means, the lever having a first limiting position established by impact of its work arm against thefirst jaw member, the lever work arm and link being substantially aligned, in eflect, in such lever position and the second jaw member being in its clamping position, or the link being alternatively approximately transverse to the work arm, and the second jaw member being in its released position, the lever having a second limiting position established by an alignment of the link and actuating arm, in which the second jaw member is in an intermediate position, the second jaw member being actuable by the lever to either of its said spaced positions according as the link and actuating arm are relatively diverged to one side or the other of their alignment, whereby back and forth oscillations of the lever alternately establish the limiting positions of the second jaw member.

5. A toggle clamp as set forth in claim 4, the first jaw member being disposed between said lever and the second jaw member in the clamping position of the second jaw member.

References Cited in the file of this patent UNITED STATES PATENTS 

